CN111925268B

CN111925268B - Production method of n-heptane

Info

Publication number: CN111925268B
Application number: CN202010347762.4A
Authority: CN
Inventors: 田炅真; 姜秀吉
Original assignee: Aiskai Zhixin Co ltd; SK Innovation Co Ltd
Current assignee: Aiskai Zhixin Co ltd; SK Innovation Co Ltd
Priority date: 2019-05-13
Filing date: 2020-04-28
Publication date: 2024-04-12
Anticipated expiration: 2040-04-28
Also published as: CN111925268A; US10975003B2; KR102156622B1; EP3738946B1; US20200361837A1; EP3738946A1; JP2020186224A

Abstract

There is provided a process for producing n-heptane, the process comprising: a step of distilling a feed comprising a C6-hydrocarbon component, a C7 hydrocarbon component, and a c8+ hydrocarbon component, removing the C8+ hydrocarbon component and the C6-hydrocarbon component, and separating the C7 hydrocarbon component; a step of feeding the separated C7 hydrocarbon component to a hydrogenation unit and hydrogenating the separated C7 hydrocarbon component; a step of feeding the hydrogenated C7 hydrocarbon component to a Simulated Moving Bed (SMB) unit and separating the hydrogenated C7 hydrocarbon component into an extract containing n-heptane and a raffinate containing other components; and a step of distilling the extract in an extract column and separating n-heptane, wherein the purity of the produced n-heptane is 98% by weight or more.

Description

Production method of n-heptane

Cross Reference to Related Applications

The present application claims priority from korean patent application No. 10-2019-0055404 filed on the date 5 month 13 of 2019 to the korean intellectual property office according to 35u.s.c. ≡119, which patent application is incorporated herein by reference in its entirety.

Technical Field

The following disclosure relates to a process for producing n-heptane.

Background

N-heptane having a purity of 99 wt% or more is a high-value solvent product used as a pharmaceutical ingredient extractant and as a solvent used in a coating process of a display such as an Organic Light Emitting Diode (OLED), a Styrene Butadiene Rubber (SBR) polymerization process, and the like.

In addition, n-heptane having a purity of 99.8% by weight or more is used for a reference fuel used in a measurement test of octane number of gasoline, is used for an analysis device for High Performance Liquid Chromatography (HPLC), and is used for a solvent for pharmaceutical use, and a product thereof is sold separately from an n-heptane product having a purity of 99% by weight or more.

An aromatic compound treatment process (benzene, toluene and xylene (BTX) process) as a petrochemical process is a process for producing benzene, toluene and xylene from naphtha subjected to a desulfurization process. The desulfurized naphtha, which is a raw material used in the BTX process, is mixed with normal paraffins.

Such normal paraffins are commercially valuable for use as described above, and are advantageous in aromatics processing processes because the yield of aromatics increases after removal of normal paraffin components.

Thus, in the case where the desulfurized naphtha is subjected to normal paraffin removal or the components contained therein are converted into high-value normal paraffin components and then the desulfurized naphtha is used as a feedstock in an aromatics treatment process, the yield capacity in the overall process can be greatly improved.

Disclosure of Invention

Embodiments of the present invention are directed to providing an n-heptane production method capable of preventing a compromise between an increase in purity and a decrease in yield, while being capable of producing high-purity n-heptane from desulfurized naphtha and also capable of producing ultra-high-purity n-heptane having 99.8 wt% or more.

In one aspect, the method for producing n-heptane comprises: a step of distilling a feed comprising a C6-hydrocarbon component, a C7 hydrocarbon component, and a c8+ hydrocarbon component, removing the C8+ hydrocarbon component and the C6-hydrocarbon component, and separating the C7 hydrocarbon component; a step of feeding the separated C7 hydrocarbon component to a hydrogenation unit and hydrogenating the separated C7 hydrocarbon component; a step of feeding the hydrogenated C7 hydrocarbon component to a Simulated Moving Bed (SMB) unit and separating the hydrogenated C7 hydrocarbon component into an extract containing n-heptane and a raffinate containing other components; and a step of distilling the extract in an extract column and separating n-heptane, wherein the purity of the produced n-heptane is 98% by weight or more.

The n-heptane production process may further comprise the step of recycling a portion of the n-heptane separated in the extract column to the front end of the SMB unit.

More specifically, the method for producing n-heptane may further comprise: recycling a portion of the n-heptane separated in the extract column to a step between the rear end of the hydrogenation unit and the front end of the SMB unit.

In the recycling step, the recycling rate may be 30% to 60%.

More specifically, the purity of the n-heptane produced may be 99.8 wt% or more.

The step of distilling a feed comprising C6-hydrocarbon components, C7 hydrocarbon components, and c8+ hydrocarbon components, removing the C8+ hydrocarbon components and the C6-hydrocarbon components, and separating the C7 hydrocarbon components may comprise: a step of distilling and removing a c8+ hydrocarbon component in a first distillation column; a step of distilling and removing the C6-hydrocarbon component in a second distillation column.

The step of distilling a feed comprising C6-hydrocarbon components, C7 hydrocarbon components, and c8+ hydrocarbon components, removing the C8+ hydrocarbon components and the C6-hydrocarbon components, and separating the C7 hydrocarbon components may comprise: a step of distilling and removing a C6-hydrocarbon component in a first distillation column; a step of distilling and removing the c8+ hydrocarbon component in a second distillation column.

The feed comprising the C6-hydrocarbon component, the C7 hydrocarbon component, and the c8+ hydrocarbon component may be a desulfurized naphtha.

The feed comprises 3 wt.% to 10 wt.% C6-normal paraffins, 5 wt.% to 15 wt.% C7 normal paraffins, 5 wt.% to 20 wt.% c8+ normal paraffins, and the balance comprising naphthenes, isoparaffins, and aromatic components, relative to 100 wt.% of the total weight of the feed comprising C6-hydrocarbon components, C7 hydrocarbon components, and c8+ hydrocarbon components.

In another general aspect, n-heptane produced by an n-heptane production process is provided.

Other features and aspects will become apparent from the following detailed description, the accompanying drawings, and the claims.

Drawings

Fig. 1 is a process diagram of an n-heptane production method according to an exemplary embodiment of the present invention.

Fig. 2 is a process diagram of an n-heptane production method according to an exemplary embodiment of the present invention.

FIG. 3 is a process diagram of the n-heptane production method of comparative example 1.

FIG. 4 is a process diagram of the n-heptane production method of comparative example 2.

[ detailed description of the essential elements ]

10: first distillation column 11: second distillation column

20: hydrogenation apparatus 30: third distillation column

40: stripping device 50: simulated moving bed device

51: extract column 52: raffinate tower

53: desorbent reservoir 60: dryer

101: recirculation pipe

Detailed Description

Unless defined otherwise, all terms (including technical and scientific terms) used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Throughout this specification, unless explicitly stated to the contrary, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of other elements but not the exclusion of any other elements. In addition, singular forms include plural forms unless the context clearly indicates otherwise.

Unless specifically defined otherwise in the present specification, the term "high purity n-heptane" may refer to n-heptane having a purity of 98% by weight or more, more specifically 99% by weight or more.

Unless specifically defined otherwise in the present specification, the term "ultra-high purity n-heptane" may refer to n-heptane having a purity of 99.8 wt% or more.

The present invention relates to a process for producing n-heptane from desulfurized naphtha.

In particular, according to the n-heptane production method according to an exemplary embodiment of the present invention, high-purity n-heptane used as a pharmaceutical ingredient extracting agent and as a solvent used in a coating process of a display such as an Organic Light Emitting Diode (OLED), a styrene-butadiene rubber (SBR) polymerization process, or the like may be produced.

Further, according to the n-heptane production method according to the exemplary embodiment of the present invention, it is possible to produce n-heptane having an ultra-high purity of 99.8 wt% or more in high yield, which can be used for a reference fuel used in a measurement test of octane number, for an analysis device for High Performance Liquid Chromatography (HPLC), and for a solvent for pharmaceutical use.

The n-heptane production method according to an exemplary embodiment of the present invention includes: a step of distilling a feed comprising a C6-hydrocarbon component, a C7 hydrocarbon component, and a c8+ hydrocarbon component, removing the C8+ hydrocarbon component and the C6-hydrocarbon component, and separating the C7 hydrocarbon component; a step of feeding the separated C7 hydrocarbon component to a hydrogenation unit and hydrogenating the separated C7 hydrocarbon component; a step of feeding the hydrogenated C7 hydrocarbon component to a Simulated Moving Bed (SMB) unit and separating the hydrogenated C7 hydrocarbon component into an extract containing n-heptane and a raffinate containing other components; and a step of distilling the extract in an extract column and separating n-heptane.

The n-heptane production process according to an exemplary embodiment of the present invention is a process for producing n-heptane from a feed comprising a C6-hydrocarbon component, a C7 hydrocarbon component, and a c8+ hydrocarbon component. In the n-heptane production process, the hydrogenation and SMB processes may be performed sequentially after separating out only the C7 hydrocarbon component.

The hydrogenation and SMB process are sequentially performed on the feed so that n-heptane having a high purity of 98 wt% or more, more specifically 99 wt% or more, can be produced.

In addition, n-heptane is produced by removing aromatic components and the like by hydrogenation in advance and performing the SMB process only on non-aromatic components, so that n-heptane can be produced while changing specific conditions of the SMB process without considering specific properties of aromatic components and the like, and high-purity n-heptane can be produced after performing the SMB process without an additional distillation process.

Thus, the process can be not only very easy to operate and manage, but also simplified, which can reduce the cost of the overall process.

In particular, in the case of hydrogenation after performing the SMB process, an aromatic component is inevitably mixed in the extract containing a large amount of n-heptane as a desired product in the SMB process, which reduces the operation efficiency of the SMB process. Therefore, it is necessary to set the conditions of the SMB process to minimize the decrease in the operation efficiency, and to add a separation process such as an additional distillation process because the purity of n-heptane cannot be sufficiently improved due to a large amount of residual components other than n-heptane even after the hydrogenation is performed, and the removal of an aromatic compound hydrogenation product having properties different from those of n-heptane must be performed.

In contrast, in the case where hydrogenation is performed in advance, the aromatic component is removed in advance, and thus the aromatic component is not present in the extract in the subsequent SMB process. Thus, the SMB process can be easily performed, and high-purity n-heptane can be produced without an additional separation process after hydrogenation is performed.

The n-heptane production method according to an exemplary embodiment of the present invention may further include a step of recycling a portion of the n-heptane separated in the extract column to the front end of the SMB device.

By further including the recycling step, n-heptane having an ultra-high purity of 99.8 wt% or more can be produced in high yield.

Specifically, in the n-heptane production method according to the exemplary embodiment of the present invention, in order to increase the purity of n-heptane to 99.8 wt% or more, it is necessary to increase the purity of n-heptane in the feed added to the SMB process.

However, in order to increase the purity of n-heptane in the feed to the SMB process without recycling, the throughput in the previous process must be reduced, thus reducing the throughput in the SMB process. Therefore, the yield of n-heptane having a purity of 99.8 wt% or more may be reduced to such an extent that n-heptane is practically unusable industrially.

That is, since the purity of n-heptane in the feed added to the SMB process and the throughput in the SMB process are in a trade-off relationship, a solution for solving such a trade-off relationship is required.

To this end, the n-heptane production method according to an exemplary embodiment of the present invention may further include a step of recycling a portion of the n-heptane separated in the extract column to the front end of the SMB device.

That is, a part of the n-heptane separated in the extract column after the SMB process is recycled to the front end of the SMB apparatus, so that the purity of the n-heptane in the feed added to the SMB process can be improved. Thus, the purity of the final n-heptane product can be increased without reducing the throughput of the overall process.

More specifically, the n-heptane production process according to an exemplary embodiment of the present invention may further include a step of recycling a portion of the n-heptane separated in the extract column to between the rear end of the hydrogenation apparatus and the front end of the SMB apparatus.

It may be more advantageous to recycle a portion of the n-heptane separated in the extract column between the rear end of the hydrogenation unit and the front end of the SMB unit.

This is due to the fact that: in the case where a part of n-heptane is recycled to the front end of the hydrogenation apparatus, as the throughput between the hydrogenation process and the SMB process increases, the amount to be treated in a separation process such as a distillation process and a stripping process increases between the hydrogenation process and the SMB process, and thus the process cost may be unnecessarily increased.

Meanwhile, in the recycling step, the recycling rate may be 30% to 60%, and more particularly 35% to 55%. In order to produce a product while maintaining the processing capacity in the process at a predetermined level or more, it is necessary to maintain the recirculation rate at an appropriate level. When the recycle rate is low, the yield of n-heptane may be reduced due to the reduced throughput in the process.

Within this range, a part of the n-heptane separated in the extract column is recycled to the front end of the SMB device, so that n-heptane having an ultra-high purity of 99.8 wt% or more can be produced without reducing the throughput of the entire process.

Here, the recycling rate may refer to a recycling amount of 100% by weight of n-heptane with respect to the total weight of the n-heptane-containing effluent discharged from the extract column.

In the n-heptane production process according to an exemplary embodiment of the present invention, the feed comprising the C6 hydrocarbon component, the C7 hydrocarbon component, and the c8+ hydrocarbon component may be a desulfurized naphtha.

That is, the feed comprising the C6-hydrocarbon component, the C7 hydrocarbon component, and the c8+ hydrocarbon component may be a desulfurized naphtha obtained by subjecting naphtha separated from crude oil to a desulfurization process.

The desulfurized naphtha can comprise 3 wt.% to 10 wt.% of C6-normal paraffins, 5 wt.% to 15 wt.% of C7 normal paraffins, 5 wt.% to 20 wt.% of c8+ normal paraffins, and the balance comprising naphthenes, isoparaffins, and aromatic components, relative to 100 wt.% of the total weight of the desulfurized naphtha.

More specifically, the desulfurized naphtha may comprise 3 wt.% to 10 wt.% of C6-normal paraffins, 5 wt.% to 15 wt.% of C7 normal paraffins, 5 wt.% to 20 wt.% of c8+ normal paraffins, 20 wt.% to 35 wt.% of naphthenes, 25 wt.% to 40 wt.% of isoparaffins, and 5 wt.% to 15 wt.% of aromatic components, relative to 100 wt.% of the total weight of the desulfurized naphtha.

In the n-heptane production process according to an exemplary embodiment of the present invention, distilling a feed comprising a C6-hydrocarbon component, a C7-hydrocarbon component, and a c8+ hydrocarbon component, the step of removing the C8+ hydrocarbon component and the C6-hydrocarbon component and separating the C7-hydrocarbon component may include: a step of distilling and removing a c8+ hydrocarbon component in a first distillation column; and a step of distilling and removing the C6-hydrocarbon component in a second distillation column.

The C6-hydrocarbon component and the c8+ hydrocarbon component may be removed from the feed containing the C6-hydrocarbon component, the C7 hydrocarbon component and the c8+ hydrocarbon component by distillation. In this case, the order of removing the C6-hydrocarbon component and the c8+ hydrocarbon component is not limited to a specific order.

That is, the terminology of the first distillation column and the second distillation column is given for convenience only, and the serial numbers thereof do not indicate the order. The c8+ hydrocarbon component may be removed after the C6-hydrocarbon component is removed. Alternatively, the C6-hydrocarbon component may be removed after the removal of the c8+ hydrocarbon component.

In the n-heptane production method according to the exemplary embodiment of the present invention, distillation may be performed by a well-known distillation method, and the number of stages of the distillation column may be adjusted as needed. As a non-limiting example, a single or multiple distillation columns may be used that include a bottom reboiler and an overhead condenser and have a progression of 10 to 100.

In the n-heptane production process according to the exemplary embodiment of the present invention, the hydrogenation may be performed by a process of hydrogenating unsaturated hydrocarbons (such as aromatic components and olefins) into saturated hydrocarbons. Since the reactor temperature and the outlet temperature may be increased due to the reaction heat generated during hydrogenation when the reactants are injected into the hydrogenation reactor, it is preferable that the reactants to be added are injected into the hydrogenation reactor after the hydrogenation reactor temperature is lowered. The specific hydrogenation method may be carried out by a method known in the art, and is not limited to a specific method.

In the n-heptane production method according to the exemplary embodiment of the present invention, the SMB process using the SMB apparatus may be performed by: using a device comprising an adsorption bed filled with zeolite-based adsorbent and an on-off valve, a component having high selectivity for the adsorbent is adsorbed onto the adsorbent and extracted as an extract, and the residual component is discharged as a raffinate. However, the present invention is not necessarily limited thereto.

Fig. 1 and 2 are process diagrams of an n-heptane production method according to an exemplary embodiment of the present invention.

Hereinafter, an n-heptane production method according to an exemplary embodiment of the present invention will be described with reference to fig. 1 and 2.

First, as shown in fig. 1, desulfurized naphtha is added to the first distillation column 10 and c8+ hydrocarbon components are removed through the lower portion of the first distillation column, and then C7-hydrocarbon components are separated through the upper portion of the first distillation column.

Thereafter, the C7-hydrocarbon component is added to the second distillation column 11, and the C6-hydrocarbon component is removed through the upper portion of the second distillation column, and then the C7-hydrocarbon component is separated through the lower portion of the second distillation column.

The separated C7 hydrocarbon components are added to the hydrogenation unit 20 and unsaturated hydrocarbon components (e.g., aromatic components and olefin components) are converted to saturated hydrocarbon components by hydrogenation.

Alternatively, as depicted in fig. 2, the desulfurized naphtha is added to the first distillation column 10 and the C6-hydrocarbon component is removed through an upper portion of the first distillation column, followed by separation of the c7+ hydrocarbon component through a lower portion of the first distillation column.

Thereafter, the c7+ hydrocarbon component is added to the second distillation column 11, and the c8+ hydrocarbon component is removed through the lower portion of the second distillation column, and then the C7 hydrocarbon component is separated through the upper portion of the second distillation column.

Thereafter, for the hydrogenation effluent, a distillation process via the third distillation column 30 and/or a process of additionally removing a liquid component having a low boiling point by a stripping process via the stripping device 40 may be additionally performed as needed. However, in the n-heptane production method according to the exemplary embodiment of the present invention, these processes may be additionally performed as needed, and do not necessarily have to be performed.

Next, the hydrogenated effluent was added to a Simulated Moving Bed (SMB) unit 50, with n-heptane separated as extract through the upper portion of the SMB unit and other components separated as raffinate through the lower portion of the SMB unit. In this case, desorbent may be mixed with the extract and raffinate.

Here, the raffinate may be separated in a raffinate column 52 into desorbent (through an upper portion of the raffinate column) and raffinate (through a lower portion of the raffinate column). The separated raffinate may be used as a feedstock in an aromatics processing process or may be used as an oil for blending gasoline.

Desorbent exiting the upper portion of the raffinate column may again be added to the SMB unit 50 via desorbent reservoir 53.

The extract exiting the upper portion of the SMB unit 50 contains separated n-heptane. The extract may be separated in extract column 51 into a desorbent (through the upper portion of the extract column) and an extract comprising n-heptane (through the lower portion of the extract column).

Desorbent exiting the upper portion of the extract column may again be added to the SMB device 50 via desorbent reservoir 53.

N-heptane withdrawn from the lower part of the extract column can be obtained as final product.

Meanwhile, herein, in order to increase the purity of the final n-heptane product to 99.8 wt% or more, the n-heptane discharged from the lower portion of the extract column 51 may be recycled between the rear end of the hydrogenation apparatus 20 and the front end of the SMB apparatus 50 through a recycling pipe 101 connected to a discharge pipe connected to the lower portion of the extract column 51.

Therefore, as described above, n-heptane having an ultra-high purity of 99.8 wt% or more can be produced without reducing the throughput in the entire process.

As an example, a recycling entry position of n-heptane discharged from the lower part of the extract column 51 is shown in fig. 1, and the recycling entry position of the discharged n-heptane is not particularly limited as long as it is located between the rear part of the hydrogenation apparatus 20 and the front end of the SMB apparatus 50.

Hereinafter, preferred embodiments of the present invention and comparative examples will be described. However, the following examples are only preferred embodiments of the present invention, and the present invention is not limited to the following examples.

Example 1

N-heptane was produced according to the process shown in fig. 1 by using the desulfurized naphtha subjected to the desulfurization process as a raw material. The recycle rate obtained by recycling the effluent containing n-heptane discharged from the extract column to the front end of the SMB apparatus was 45%.

The composition of the desulfurized naphtha used therein is shown in table 1.

TABLE 1

	C6-n-Paraffin	C7 n-Paraffin	C8+ n-paraffins	Cycloalkane (CNS)	Isoparaffins	Aromatic component	Total amount of
								(content, wt.%)	8.45	9.90	7.72	28.80	35.28	9.85	100

The purity of the finally obtained n-heptane was 99.86% by weight.

Example 2

N-heptane was produced in the same manner as in example 1 except that n-heptane was produced according to the process shown in fig. 2.

The purity of the finally obtained n-heptane was 99.85% by weight.

Example 3

N-heptane was produced in the same yield as in example 1 in the same manner as in example 1 by using a desulfurized naphtha having the composition shown in table 1 as a raw material without recycling an effluent containing n-heptane discharged from the extract column.

The purity of the finally obtained n-heptane was 99.36% by weight.

Comparative example 1

By using the desulfurized naphtha having the composition shown in table 1 as a raw material, n-heptane was produced in the same yield as in example 1 according to the process shown in fig. 3.

The purity of the finally obtained n-heptane was 99.51 wt%.

In the case where the SMB process and the hydrogenation process as shown in fig. 3 are performed, in order to produce n-heptane having a purity of 99 wt% or more, the distillation process 12 must be performed in the final stage.

Comparative example 2

By using the desulfurized naphtha having the composition shown in table 1 as a raw material, n-heptane was produced in the same yield as in example 1 according to the process shown in fig. 4.

The purity of the finally obtained n-heptane was 95.12% by weight.

In the case where the SMB process and the hydrogenation process as shown in fig. 4 are performed, n-heptane having a purity of 98 wt% or more, more specifically 99 wt% or more, cannot be produced when no additional distillation process is performed in the final stage.

As described above, according to exemplary embodiments of the present invention, there is provided an n-heptane production method capable of preventing a compromise between an increase in purity and a decrease in yield, while being capable of producing n-heptane having a high purity from desulfurized naphtha and also producing n-heptane having an ultra-high purity of 99.8 wt% or more.

Further, according to the n-heptane production method of the exemplary embodiment of the present invention, an n-heptane product is produced from desulfurized naphtha used as a raw material in an aromatic compound treatment process (BTX process), and thus, the profitability of the BTX process can be improved. In addition, in the case where the desulfurized naphtha from which the normal paraffins are removed by the production method of the present invention is used as a raw material in the BTX process, the yield in the BTX process can also be improved.

Claims

1. A process for producing n-heptane, comprising:

a step of distilling a feed comprising a C6-hydrocarbon component, a C7 hydrocarbon component, and a c8+ hydrocarbon component, removing the c8+ hydrocarbon component and the C6-hydrocarbon component, and separating the C7 hydrocarbon component;

a step of feeding the separated C7 hydrocarbon component to a hydrogenation apparatus and hydrogenating the separated C7 hydrocarbon component;

a step of feeding the hydrogenated C7 hydrocarbon component to a simulated moving bed apparatus and separating the hydrogenated C7 hydrocarbon component into an extract containing n-heptane and a raffinate containing other components;

a step of distilling the extract in an extract column and separating the n-heptane, and

a step of recycling a part of the n-heptane separated in the extract column to between the rear end of the hydrogenation unit and the front end of the simulated moving bed unit;

wherein in the step of recycling, the recycling rate is 30% to 60%, and

wherein the purity of the n-heptane produced is 99.8 wt% or more.

2. The n-heptane production process of claim 1, wherein the step of distilling a feed comprising a C6-hydrocarbon component, a C7 hydrocarbon component, and a c8+ hydrocarbon component, removing the C8+ hydrocarbon component and the C6 hydrocarbon component, and separating the C7 hydrocarbon component comprises:

a step of distilling and removing the c8+ hydrocarbon component in a first distillation column; and

a step of distilling and removing the C6-hydrocarbon component in a second distillation column.

3. The n-heptane production process of claim 1, wherein the step of distilling a feed comprising a C6-hydrocarbon component, a C7 hydrocarbon component, and a c8+ hydrocarbon component, removing the C8+ hydrocarbon component and the C6 hydrocarbon component, and separating the C7 hydrocarbon component comprises:

a step of distilling and removing the C6-hydrocarbon component in a first distillation column; and

a step of distilling and removing the c8+ hydrocarbon component in a second distillation column.

4. The n-heptane production process of claim 1, wherein the feed comprising C6-hydrocarbon components, C7 hydrocarbon components, and c8+ hydrocarbon components is a desulfurized naphtha.

5. The n-heptane production process of claim 1, wherein the feed comprises from 3 wt.% to 10 wt.% C6-n-paraffins, from 5 wt.% to 15 wt.% C7 n-paraffins, from 5 wt.% to 20 wt.% c8+ n-paraffins, and the balance comprising naphthenes, isoparaffins, and aromatic components, relative to 100 wt.% of the total weight of the feed comprising C6-hydrocarbon components, C7 hydrocarbon components, and c8+ hydrocarbon components.